JP4710409B2 - Compressed air inflow adjustment mechanism for pneumatic tools - Google Patents

Description

The present invention relates to a compressed air inflow adjustment mechanism in a pneumatic tool, which is supplied while adjusting an inflow amount of compressed air when compressed air is supplied from a compressed air supply source to an operating part of a tool body in a pneumatic tool.

  In a conventional pneumatic tool, when supplying compressed air from a compressed air supply source to the working part of the tool body, a trigger valve is provided between the compressed air supply source of the tool body and the working part, and the trigger lever is pulled. Control of the supply and stop of compressed air to the operating unit from a compressed air supply source using a trigger valve.

  Known trigger valve systems include a single valve system such as an air driver and an air wrench, and a pilot valve system such as a nail driver, a screw driver and a turbo driver.

  By the way, in the single pulling type valve, as shown in Patent Document 1, the trigger lever pull amount or the trigger valve valve diameter and the inflow amount of the compressed air are proportional to each other. There is an advantage that it can be supplied to the downstream side while adjusting the amount little by little.

On the other hand, in the pilot valve system, when the trigger lever pull amount reaches a certain position, the sign is switched on and off completely, so a large amount of compressed air is applied at once regardless of the trigger lever pull amount. There is an advantage that can be sent to the operating part.
Japanese Patent No. 2821921

  However, in a single-pull trigger valve, the diameter of the valve must be increased or the operating pressure range must be increased to increase the power of the pneumatic tool in order to ensure the flow rate of compressed air. There is a problem that the pulling load of the trigger valve becomes too large.

  Further, in the pilot valve type trigger valve, the inflow amount of the compressed air cannot be finely adjusted by adjusting the pulling operation of the trigger lever. For this reason, it causes air driver come-out and the like, which is a problem from the viewpoint of usability.

  The present invention solves the above-mentioned problems, incorporates the advantages of single pulling and pilot valve methods, and achieves maximum compressed air inflow and fine adjustment of inflow without increasing the pulling load of the trigger lever An object of the present invention is to provide a compressed air inflow adjustment mechanism in a pneumatic tool that can be used.

In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a compressed air supply path is formed between the compressed air supply source and the working part of the tool body, and the supply path is opened and closed to open the compressed air supply source. In the pneumatic tool for controlling the operating portion by compressed air, a intake port for compressed air is formed in the middle of the supply path, and a pilot valve for opening and closing the intake port is formed at one end of the intake port. The valve stem is slidably disposed so that the portion abuts and separates from the intake port and closes and opens the intake port. The valve stem is slidably inserted into the pilot valve, and one end of the valve stem is The bottom of the pilot valve valve housing is provided so that it can be pushed in from the outside, and the space between the bottom of the pilot valve and the valve housing is formed on the side wall of the pilot valve. The communication path is communicated with the supply path through the communication hole, and the pilot valve is held at the first position of the closed position by blocking against the atmosphere, and the valve stem is pushed in, so that the space is formed in the supply path. The pilot valve is moved to the second position of the open position by communicating with the atmosphere, and an opening / closing means for opening and closing the downstream side of the intake port is provided on the downstream side of the intake port, The pilot valve has a cylindrical shape, and as the opening / closing means, an adjustment valve that opens and closes the opening end on the downstream side of the intake port is disposed on the extension of the shaft end on the other end side of the pilot valve, and the adjustment valve is closed. The pilot valve is opened and actuated to open the upstream side of the intake port, and the adjustment valve is pushed in. And wherein the actuating opening downstream of the inlet.

According to a second aspect of the present invention, in the first aspect, instead of spring-biasing the regulating valve in the closing direction , an air passage is formed from the upstream side of the intake port of the supply passage to the back side of the regulating valve. Further, the air pressure acting on the back side of the regulating valve is biased in the closing direction of the regulating valve.

The invention according to claim 3 is the valve stem according to claim 1, wherein the pilot valve has a bottomed cylindrical shape, a choke member that changes the cross-sectional area of the supply path is disposed as the opening / closing means instead of the adjustment valve, and the valve stem The pilot valve is opened by pushing to open the upstream side of the intake port, and the downstream side of the intake port is opened by the choke member.

According to a fourth aspect of the present invention, in the first aspect, on the downstream side of the pilot valve of the intake port, the opening / closing means is constituted by a cylindrical body smaller than the intake port and supplied to the side wall instead of the adjustment valve. An auxiliary intake having an opening that opens on the downstream side of the road and a ball valve that opens and closes the auxiliary intake are arranged, and the tip of the auxiliary intake is the end of the valve stem insertion port of the pilot valve that is closed The ball valve is disposed on the extension of the shaft end on the other end side of the pilot valve, the ball valve is spring-biased in the closing direction, and the ball valve is pushed by pushing the valve stem. After the push-in operation is performed to open the auxiliary intake port, the pilot valve is opened to activate the intake port .

According to the first aspect of the present invention, when the pilot valve is moved to the second position by the pushing of the valve stem and operated to open, the upstream side of the intake port opens, but the downstream side of the intake port is adjusted. Since the valve is provided, the compressed air does not flow at once. However, the regulating valve is only spring-biased in the closing direction, and in the unsealed state, the compressed air supplied from the upstream side of the intake port is regulated downstream without having to push the regulating valve. The valve is opened slightly against the spring bias, and compressed air flows in small portions. Furthermore, by finely adjusting the push-in adjustment degree of the adjustment valve, the adjustment valve is actively pushed in to open the downstream side of the intake port. As described above, the inflow amount of the compressed air can be finely adjusted even by the pilot valve method.

  When tightening screws using a high-power air motor, the output can be reduced in applications where the tightening load is small, such as small screw operations or the beginning of screw tightening, and the screw tightening process can handle changes in tightening load smoothly. In contrast to this, the invention according to claim 1 requires a fine output adjustment function, while ensuring a flow rate of compressed air that can be used for applications with a small tightening load in a high-output pneumatic tool. Since the trigger load can be reduced and the inflow adjustment of the supply air by the stroke is possible, the air motor can be used at high output, which increases the work efficiency of the operator and is difficult to tighten with a low output pneumatic tool. Bolts and screws can be fastened in high load applications.

  According to the second aspect of the invention, it is possible to achieve the maximum amount of compressed air inflow and fine adjustment of the amount of inflow without increasing the pulling load of the trigger lever. In addition, operability is good and it is hard to get tired.

According to the invention according to claim 3, since it is a combination of the single pulling system and the pilot valve system , it is possible to finely adjust a flow passage of a large amount of compressed air at a time by adjusting the cross-sectional area of the supply passage by the choke member. You can also.

According to the invention of claim 4, since the ball valve is first pushed by pushing the valve stem, the auxiliary intake is opened and compressed air can be supplied little by little. Thereafter, when the valve stem is moved to the second position, the compressed air suddenly flows in. Therefore, as in the case of the invention according to claim 1, it is possible to secure a flow rate of compressed air that can be used for applications with a small tightening load in a high-power pneumatic tool, and in a fine adjustment region in screwing work. since it is possible to rapidly rotate the screw after engaging the tip of the screwdriver into the screw head, it is possible to perform work quickly.

  FIG. 1 is a longitudinal sectional side view showing an impact driver as an example of a pneumatic tool operating with compressed air in a high pressure region. The impact driver 1 includes a tool body 2 in which a handle portion 3 for gripping the impact driver 1 during work is integrally formed toward the rear side, and an impact driver is provided at one end side in the tool body 2. An air motor 4 (actuating portion) that is rotationally driven by compressed air having a pressure in a high pressure region supplied into 1 is disposed, and is connected to the output shaft 5 of the air motor 4 at the other end in the tool body 2. The impact mechanism 6 is accommodated. The output shaft 5 of the air motor 4 is connected to the impact hammer 7 of the impact mechanism 6, and the impact hammer 7 is driven to rotate by the air motor 4 so that the anvil 8 is hit by the impact hammer 7 and impacts the anvil 8. Torque is transmitted. The tip of the anvil 8 is disposed so as to protrude from the end of the tool body 2 to the outside of the tool body 2, and a chuck portion 9 for detachably attaching a driver bit to the tip of the anvil 8 is provided. Is formed.

  The handle portion 3 is formed in a hollow shape. In the hollow portion of the handle portion 3, an air chamber 10 that stores compressed air supplied from a compressed air supply source A, and an air motor 4 after driving the air motor 4. An exhaust chamber 11 for storing exhaust air exhausted from is formed in parallel. An air plug 12 for connecting a socket attached to the end of an air hose connected to the compressed air supply source A to the impact driver 1 is attached to the rear end of the air chamber 10. Compressed air is supplied to the air chamber 10.

  Compressed air exhausted from the air motor 4 by driving the air motor 4 is introduced into the exhaust chamber 11 from the exhaust port 14 formed in the filter case 13 formed at the rear end portion of the handle portion 3 into the atmosphere. Is discharged. An exhaust filter 15 is accommodated inside the filter case 13 in order to reduce the flow rate of compressed air exhausted from the exhaust port 14 to the atmosphere and to blow up dust and wood chips at the work site. The exhaust filter 15 is formed in a cylindrical shape by winding a fine metal mesh in a spiral shape, and is accommodated in the cylindrical filter case 13.

  A supply path for supplying compressed air supplied into the air chamber 10 to the air motor 4 is provided at the base of the handle portion 3 located between the compressed air supply source A and the operating portion (air motor 4) of the tool body 2. 18 is formed, and a compressed air inflow adjusting mechanism 20A for controlling the operation of the air motor 4 by the compressed air by opening and closing a compressed air intake port 19 provided in the supply path 18 is provided.

  As shown in detail in FIGS. 2A, 2B and 2C, the compressed air inflow adjusting mechanism 20A includes an adjusting valve 21 disposed on the downstream side of the intake motor 19 where the air motor 4 is located, and an air chamber. 10 and a pilot valve 22 arranged on the upstream side. Note that both the upstream and downstream opening ends of the intake port 19 are chamfered to form a conical slope.

  The adjusting valve 21 is formed by integrally forming a sliding body 21b on the back side of a truncated cone-shaped valve body 21a. The sliding body 21b is slidable in the valve cylinder 24 with an O-ring 23 attached to the outer periphery. The valve main body 21a is always in contact with the opening end of the intake port 19 and is biased in a direction to close the intake port 19 by a spring 25 provided in the valve housing 24 and the sliding body 21b.

  By the way, an air passage 26 is detoured from the upstream side of the intake port 19 to the back side of the regulating valve 21 so that the compressed air from the air passage 26 acts on the end surface of the sliding body 21b on the back side of the regulating valve 21. It is configured.

  Next, the pilot valve 22 is formed in a cylindrical shape. The pilot valve 22 is slidably disposed in the valve housing 27, and the valve stem 28a is slidably inserted therein. It is provided on the extension on the upstream side of the axis. The valve housing 27 is open to the supply path 18. A through hole 30 is formed at the bottom of the valve housing 27.

  An O-ring 31 is wound around the peripheral edge of the pilot valve 22, and at the top dead center, the O-ring 31 abuts the opening end on the upstream side of the intake port 19 to close the intake port 19 and shut off the air supply. At the bottom dead center, the intake port 19 is opened away from the opening end to supply air. The pilot valve 22 is formed with a small diameter at the top, a larger diameter at the middle and a large diameter at the bottom, with the middle step and the step on the base side. Yes. A communication hole 34 communicating with the inside of the supply path 18 is formed on the side wall near the upper middle side.

  The valve stem 28 a is disposed so as to pass through the pilot valve 22, the upper end of the valve stem 28 a is disposed so that the adjusting valve 21 can be pushed in, and the lower end of the valve stem 28 a is the bottom through hole 30 of the valve housing 27. An operation unit (trigger lever) 35 that can be pushed from the outside is provided. The valve stem 28 a is provided with an upper O-ring 36, an intermediate O-ring 37, and a lower end O-ring 38.

The path for the pilot valve 22, the space S between the bottom and the valve housing 27 of that is, communicating a first position communicating with the supply passage 18 (the position of FIG. 2 (a)), the atmospheric At the same time, the other end of the valve stem 28a is moved to a second position where the adjustment valve 21 can be pushed ( the position shown in FIG. 2C). The first position is a closed position, in which the intermediate O-ring 37 opens the space S in the communication hole 34 of the pilot valve 22, and the lower end O-ring 38 is fitted in the through-hole 30 and closed. The second position is the open position, the intermediate O-ring 37 of the valve stem 28 a closes the communication hole 34 of the pilot valve 22, and the lower end O-ring 38 opens the through hole 30 .

In the above structure, when no pulling the trigger lever 35, that is, when the pilot valve 22 is in the first position shown in FIG. 2 (a), because the compressed air in the lower space S of the pilot valve 22 is supplied Compressed air acts on both ends of the pilot valve 22, but the pilot valve 22 stands by at the top dead center position where the intake port 19 is blocked by the difference in diameter between the two ends.

When the trigger lever 35 is lifted by a certain amount, the valve stem 28a moves to the position shown in FIG. 5B , and the compression space S below the pilot valve 22 is opened to the atmosphere . ) And the upstream side of the intake port 19 is opened . Inlet 19 in this state is closed by the control valve 21. However, since the regulating valve 21 is only spring-biased in the closing direction and the downstream side of the intake port 19 is not sealed, it is supplied from the upstream side of the intake port 19 even if the regulating valve 21 is not pushed. The compressed air can be slightly opened as shown in the left side of FIG. 3 by slightly opening the regulating valve 21 against the spring bias.

Further, when pulling the trigger lever 35, the upper end of the bets Rigareba 35 pushes the control valve 21 can be secured by an amount supply area pushed. Therefore, the operator can realize fine adjustment of the supply air flow rate depending on the pulling amount of the trigger lever 35. When the valve stem 28a is moved to the moving end, the intake port 19 is completely released, and the amount of compressed air flowing in is maximized.

  By the way, the regulating valve 21 is urged in the closing direction by the air pressure acting on the back surface of the valve body 21a (the surface surrounding the sliding body 21b) and the load by the spring 25. The compressed air from 26 can be applied to the rear end face of the regulating valve 21 and sealed with an O-ring 23 to generate a valve load. As a result, the necessary spring load can be compensated, so that the adjustment valve 21 can be kept in the air supply cutoff position even if the spring load is small. In addition, since the air supply area at the start of the pilot valve operation is determined by the setting of the area of the end face of the sliding body 21b of the regulating valve 21 and the O-ring diameter and spring load of the regulating valve 21, the initial flow rate can be stabilized. it can.

Therefore, according to the compressed air inflow adjusting mechanism 20A having the above-described configuration, as shown by a solid line in FIG. 3, fine adjustment is performed when the pilot valve 22 is in the second position, and the valve is adjusted in the fine adjustment region. stem 28a is little by little inflow in proportion to the amount of pushing the control valve 21 is increased, the inflow amount of the last compressed air is maximized.

  According to the above-described inflow adjustment mechanism, it is possible to secure the maximum inflow amount of compressed air and finely adjust the inflow amount without increasing the pulling load of the trigger lever 35.

In addition, in screw tightening work using a high-power air motor, the output can be reduced in applications where the tightening load is small, such as small screw work or the beginning of screw tightening, and the tightening process can respond to changes in the tightening load. A smooth output fine adjustment function is required. On the other hand, the inflow adjustment mechanism 20A secures a flow rate of compressed air that can be used for applications with a small tightening load in a high-output pneumatic tool. However, since the trigger load can be reduced and the inflow adjustment of the air supply by the stroke can be performed, it is possible to use the air motor at a high output, which is difficult for the operator to improve the work efficiency and the pneumatic tool with a low output. Bolts and screws can be fastened in applications with high tightening loads.

  In addition, since it has an adjustment valve 21 with a diameter difference valve and can stabilize the initial flow rate at the start of operation, the rotation failure of the air motor caused by the initial flow rate unmeasurement in the pneumatic tool using the air motor ( It is possible to prevent the compressed air from flowing down.

In this connection, as shown in FIG. 4, the vertical load of the regulating valve 21 is balanced in the stroke from when the pilot valve 22 is activated until the valve stem 28a starts to push the regulating valve 21. Thus, when the pilot valve 22 is retracted from the intake port 19, the adjustment valve 21 is set to move slightly backward, so that a constant initial flow rate range ( P in the graph of FIG. 3) can be created. Depending on the shape of the regulating valve 21, the responsiveness of the fine flow adjustment (gradient Q 1 by the one-dot chain line in the graph of FIG. 3) can be set.

  Next, FIGS. 5A and 5B show another embodiment of the inflow adjusting mechanism of compressed air, and it is assumed that it is adopted in the trigger valve of the same impact driver as FIG.

  That is, the inflow adjusting mechanism 20B includes a pilot valve 22 disposed on the upstream side of the intake port 19 and a choke member 40 provided in the supply path 18, as shown in detail in FIG. .

The basic structure of the pilot valve 22 is the same as that shown in FIGS. 2A, 2B, and 2C. The upper end of the pilot valve 22 is closed to form a bottomed cylinder , and below the valve stem 28a. Is different in that the operating lever 35 is provided as a separate unit, but the basic operation is the same. That is, the valve stem 28 b is slidably inserted into the pilot valve 22, and the valve stem 28 b is always urged by the spring 41 in the closing direction of the intake port 19, and one end of the valve stem 28 b is connected to the valve housing 27. thereby enabling push the bottom from the outside through the upper Symbol pilot valve 22, the space S between the bottom of the valve cylinder, a first position communicating with the supply passage 18 in (FIGS. 5 (a) Position) and a second position communicating with the atmosphere (position shown in FIG. 5B).

  Next, the choke member 40 is disposed on the downstream side (or upstream side) of the supply path 18, and the rotation of the disk 42 having the same outer diameter as the inner diameter of the supply path 18 is provided at the center of the supply path 18. The rotary shaft 43 is rotatably fixed to the rotary shaft 43 so that the rotary shaft 43 can be operated from the outside, and the rotary shaft 43 is rotated to change the cross-sectional area of the supply path 18. The rotation operation of the rotation shaft 43 may be performed by an appropriate button or lever (not shown).

In the above configuration, when the operation lever 35 is not pulled, that is, when the pilot valve 22 is in the first position, compressed air is supplied to both ends of the pilot valve 22 as shown in FIG. Reference numeral 22 stands by at a top dead center position where the intake port 19 is blocked by the difference in diameter between both ends. At the same time, the choke member 40 also closes the supply path 18. Next, when the trigger lever is pulled to move the pilot valve 22 to the second position in FIG. 5B, the compressed air below the pilot valve 22 is released to the atmosphere . In this condition, although the supply passage 18 is closed by the choke member 40, subsequently, when the rotation shaft 43 is slightly rotated slightly to open the supply passage 18, the compressed air in the upstream side flows into the downstream side.

  Thus, the operator can realize an arbitrary fine adjustment of the air supply flow rate by the rotation amount of the choke member 40.

  Therefore, according to the compressed air inflow adjusting mechanism 20B configured as described above, it is possible to obtain a compressed air inflow change state similar to that shown by the solid line in FIG. 3, which is the same as the compressed air inflow adjusting mechanism 20A. An effect can be obtained.

  In the above embodiment, if the choke member is fully opened in advance, a large amount of compressed air can be introduced at a time.

  6 (a), 6 (b), and 6 (c) show another embodiment of the compressed air inflow adjustment mechanism, which is adopted in the trigger valve of the same impact driver as that in FIG.

  In other words, the inflow adjusting mechanism 20C is arranged on the upstream side of the intake port 19 where the air chamber 10 is located and the auxiliary intake port located on the downstream side of the intake port 19 where the air motor 10 is located, as shown in detail in FIG. And a pilot valve 22. The opening end on the downstream side of the intake port 19 is chamfered to form a conical slope.

  The auxiliary intake port is constituted by a cylindrical body 44, and a ball valve 45 is disposed inside the cylindrical body 44. The ball valve 45 is urged by a spring 46 so as to be pressed against the opening end of the cylindrical body 44 and sealed. In addition, an opening 47 is formed in the side wall of the cylindrical body 44.

  The pilot valve 22 is formed in a cylindrical shape, and is provided on an extension on the upstream side of the axis of the ball valve 45. The pilot valve 22 itself is slidably disposed in the valve housing 27 and has a valve stem 28c slidably inserted therein. The pilot valve 22 is provided on an extension on the upstream side of the axis of the ball valve 45. ing. The valve housing 27 is open to the supply path 18. A through hole 30 is formed at the bottom of the valve housing 27.

  An O-ring 31 is wound around the peripheral edge of the pilot valve 22, and at the top dead center, the O-ring 31 abuts the opening end on the upstream side of the intake port 19 to close the intake port 19 and shut off the air supply. At the bottom dead center, the intake port 19 is opened away from the opening end to supply air. The pilot valve 22 is formed with a small diameter at the top, a larger diameter at the middle and a large diameter at the bottom, with the middle step and the step on the base side. Yes. A communication hole 34 communicating with the inside of the supply path 18 is formed on the side wall near the upper middle side.

  The valve stem 28c is disposed so as to pass through the pilot valve 22. The upper end of the valve stem 28c is disposed so that the adjusting valve 21 can be pushed in. The lower end of the valve stem 28c is the bottom through hole 30 of the valve housing 27. An operation portion 35 (trigger lever) that can be pushed from the outside is provided. An upper O-ring 37 and a lower end O-ring 38 are provided on the valve stem 28c.

The path for the pilot valve 22, the space S between the bottom and the valve housing 27 of that is, communicating a first position communicating with the supply passage 18 (the position of FIG. 6 (a)), the atmospheric It moves to the 2nd position ( position of the figure (c)) to move. In the first position, as shown in FIG. 6A, the upper O-ring 37 opens the space S in the communication hole 34 of the pilot valve 22, and the lower end O-ring 38 is fitted in the through hole 30 and closed.
Incidentally, when pushing the valve stem 28c, prior to moving the pilot valve 22 to the second position, as shown in FIG. (B), the upper O-ring 37 and the lower end O-ring 38 is in the same state as the first position The ball valve 45 can be pushed in at the end of the valve stem 28c. In the second position , the intermediate O-ring 37 closes the communication hole 34 of the pilot valve 22 and the lower end O-ring 38 opens the through hole 30.

  In the above configuration, when the trigger lever 35 is not pulled, that is, when the valve stem 28c is in the first position, the compressed air is supplied to the lower space S of the pilot valve 22 as shown in FIG. Thus, compressed air is supplied to both ends of the pilot valve 22, and the pilot valve 22 stands by at a top dead center position where the intake port 19 is blocked due to a difference in diameter between both ends.

Pulling the trigger lever 35 fixed amount, the valve stem 28c as shown in FIG. (B) is to move. At this time, the pilot valve 22 is maintained in the same state, but there is room for the upper end of the valve stem 28c to push the ball valve 45, so that the auxiliary supply intake 19 is opened by the amount pushed by the ball valve 45 and the compressed air is compressed. Flows into the downstream side, so that an air supply area can be secured and compressed air can be supplied little by little. The

When the trigger lever is further pulled, the valve stem 28c moves to the second position shown in FIG. 6C, so that the auxiliary intake port 44 remains open and the intake port 19 is further opened. The compressed air is released to the atmosphere. Therefore, the pilot valve 22 moves to the lower bottom dead center position, and the intake port 19 is opened. Therefore, the inflow of compressed air is maximized.

Therefore, according to the inflow control mechanism of the compressed air having the above structure, as indicated by the dotted line in FIG. 3, when the valve stem 28c is in the position of FIG. 6 (b), the fine adjustment is performed, the pilot valve 22 When the air reaches the second position , the compressed air suddenly flows in. Therefore, the same effect as the compressed air inflow adjusting mechanism 20A can be obtained.
According to the compressed air inflow adjusting mechanism of each configuration described above, the valve responsiveness is good and the mainstream pilot valve is used in a nail driver or the like, so a pneumatic tool that does not use an air motor such as a nail driver driven by air pressure Application in the field is also possible.

It is a side view of an example of a nailing machine concerning the present invention. (A) (b) (c) is an operation explanatory view of an inflow adjustment mechanism of compressed air. It is a graph which shows the relationship between the stroke of a valve stem by the inflow adjustment mechanism of compressed air, and flow volume. FIG. 5 is an operation explanatory diagram of an example in which the balance of the load at both ends of the adjusting valve is adjusted in the inflow adjusting mechanism. (A) (b) is an operation explanatory view of other compressed air inflow adjustment mechanisms. (A) (b) (c) is an operation | movement explanatory drawing of another inflow adjustment mechanism of compressed air.

DESCRIPTION OF SYMBOLS 1 Nailer 2 Body 18 Supply path 21 Adjustment valve 22 Pilot valve 28a, 28b, 28c Valve stem

Claims (4)

In a pneumatic tool for forming a compressed air supply path between a compressed air supply source and an operating part of the tool body, and opening and closing the supply path to control the operating part by compressed air from the compressed air supply source.
An intake port for compressed air is formed in the middle of the supply path, and a pilot valve for opening and closing the intake port is formed in the intake port, and one end portion of the intake valve abuts and separates from the intake port. Slidably arranged to close and open
A valve stem is slidably inserted into the pilot valve, and one end of the valve stem is provided so as to be able to be pushed from the outside through the bottom of the valve housing of the pilot valve.
A space between the bottom of the pilot valve and the valve housing is communicated with the supply path through a communication hole formed in a side wall of the pilot valve, and is shut off from the atmosphere to close the pilot valve. By holding the first position and pushing the valve stem, the space is cut off from the supply path, and the pilot valve is moved to the second position of the open position by communicating with the atmosphere.
Opening and closing means for opening and closing the downstream side of the intake port is provided on the downstream side of the intake port,
The pilot valve has a cylindrical shape, and as the opening / closing means, an adjustment valve that opens and closes the opening end on the downstream side of the intake port is disposed on the extension of the shaft end on the other end side of the pilot valve, and the adjustment valve is closed. Spring-biased in the direction,
The valve stem is pushed to open the pilot valve to open the upstream side of the intake port, and the adjustment valve is pushed to open the downstream side of the intake port. Compressed air inflow adjustment mechanism for pneumatic tools. Instead of spring-biasing the regulating valve in the closing direction, an air passage is formed from the upstream side of the intake port of the supply path to the back side of the regulating valve, and the regulation is performed by air pressure acting on the back side of the regulating valve. 2. The compressed air inflow adjustment mechanism in a pneumatic tool according to claim 1, wherein the mechanism is biased in a valve closing direction. The pilot valve has a cylindrical shape with a bottom, and instead of the adjustment valve as the opening / closing means, a choke member that changes the cross-sectional area of the supply path is disposed,
The pilot valve is opened by operating the valve stem to open the upstream side of the intake port, and the choke member is operated to open the downstream side of the intake port.
The inflow adjustment mechanism of compressed air in the pneumatic tool according to claim 1, wherein: On the downstream side of the pilot valve of the intake port, an auxiliary intake having an opening opening on the downstream side of the supply path is formed on the side wall, which is constituted by a cylinder smaller than the intake port instead of the adjustment valve as the opening / closing means. And a ball valve for opening and closing the auxiliary intake port, the tip of the auxiliary intake port is provided to close the end of the valve stem insertion port of the closed pilot valve, and the ball valve is provided to the pilot valve. Arranged on the extension of the shaft end on the other end of the ball, and spring-biasing the ball valve in the closing direction,
After the valve stem is pushed in, the ball valve is pushed in to open the auxiliary intake, and then the pilot valve is opened to open the intake.
The inflow adjustment mechanism of compressed air in the pneumatic tool according to claim 1, wherein:

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